Bluetooth is in the 2.402 GHz to 2.480 GHz range. However, maximum power output from a Bluetooth radio is 100 mW for class 1, 2.5 mW for class 2, and 1 mW for class 3 devices. Even the maximum power output of class 1 is a lower level than the lowest powered mobile phones ...

Has anyone been in the prototyping phase and pursued an experimental license? Paul mentioned that OET Bulletin No. 63 was old and dated. Is there an upate to this bulletin that someone can point me to? Thanks.

Regarding amateur radio, they're governed under part 97, and they're primary users of some of the spectrum that's open for ISM use, so you have to accept interference from them in those cases - not that it's likely you'll run into it.

900MHz is pretty quiet from an amateur radio perspective. There isn't much amateur equipment made for that band so it's mostly adapted commercial hardware. Most of the interference you could get from ham radio takes place below 450MHz and in the 1.2GHz band that's used for amateur satellties. They could theoretically dump 1500W on certain parts of 2.4GHz and 5GHz but I've never heard of anybody running more than a few watts on it with highly directional antennas.

We need a whole semester on the FCC regs....they are insurmountable. I know of people who have had their video baby monitors called out by the policee....the device was interfering with police frequencies.

Does every product with digital electronics in it have to be at least verified? If all freq are below 1.7MHz? If it just has a tiny 6-pin PIC with internal clock, but that is 4MHz, does it have to be tested?

Cordless phones, baby monitors, and who know what operate in the 900 MHz band. My experience is that this band is very noisy in urban areas. And, if you try to operate with much power and/or gain, you will interfer with these devices. I suspect that they have poor (very unselective) receivers, and aren't prepared to have me operating a 500 mw transmitter with a fair amount of antenna gain next door.

For those of you just joining us, today's questions are: 1) Has anyone listening read through Part 15? If so, from which year, and have you been aware of changes? 2) Has anyone listening worked with isotropic and directional antennas? and 3) Has anyone listening used the 433MHz band in North America and if so, what is your application?

I thought isotropic was a theoretical construct. I assume that omnidirectional is the closest there is to an isotropic radiator, (except maybe for quadrafilar helix antenna, which might be half of an isotropic radiator). But, I'm a software guy, not a EE. And, yes, I have used both onmidirectional and directional antennas.

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I have hard copies of CFR 47 parts 0 to 19 and parts 40 to 69. But they are dated 1994. Are these outdated, or are FCC regs still the same? Or are there new regulations, but they are found in a different book?

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